严蔚敏：数据结构题集（C语言版）的海龟作图题

#include "graphics.h"
#include "math.h"
#include "stdio.h"
#include "conio.h"
#include "bios.h"
#include "dos.h"
#include "io.h"

char key_state[128],key_pressed[128];
void interrupt far (*OldInt9Handler)();

enum modes {AUTO, HIGH};
enum bool {FALSE=0, TRUE=1};
#define MODE enum modes
#define BOOL enum bool
#define K_ENTER 0x1c
#define K_DOWN 0x50
#define K_UP 0x48
#define K_SPACE 0x39
#define K_ESC 0x01
#define K_C 0x2e
#define K_A 0x1e
#define K_X 0x2d
#define UP 0
#define DOWN 1
#define PI 3.1415
#define MODE_KEY 0
#define MODE_CMD 1
#define MAX_CMD_NUM 15

/*Instruction define*/
#define EXIT 0
#define CHM 1
#define PU 2
#define PD 3
#define CHC 4
#define CHHT 5
#define ADTH 6
#define FW 7
#define BW 8
#define CLR 9
#define CHP 10

enum hlpmsg{ALL_CMD, IN_ERROR, PU_OK, PD_OK, CHC_OK, CHP_OK, CHM_OK,
            FW_OK, BW_OK, CHHT_OK, ADTH_OK, CLR_OK, M_KEY, IN_COLOR,
            IN_POS, IN_HEAD, IN_STEPS};
#define HLPMSG enum hlpmsg
typedef int penState;
typedef struct{float v,h;}aPoint;
typedef struct
{
    float heading;
    penState  pen;
    int       color;
    aPoint    Pos;
}newTurtle;

newTurtle turtle;
char GMODE=MODE_CMD;
char CmdWords[MAX_CMD_NUM][4]={